Many users carry computing devices such as laptops, mobile telephones, tablets, and media players throughout any given day. Some of these computing devices are equipped with global positioning system (GPS) receivers to provide positioning services to the users. These computing devices determine a current position for use in filtering search results (e.g., nearby restaurants), driving directions, and the like. When GPS service is unavailable or not effective (e.g., when the computing devices are indoor or when the computing devices lack a GPS receiver), some of the computing devices rely on other forms of position determination such as beacon-based positioning services. The accuracies of some existing beacon-based positioning services, however, may not meet the requirements of a given user scenario.